Data concerning the chemical and physical properties of the carcinogenic N-nitroso compounds will be collected. Specific emphases will include studies of: a) deuterium isotope effects on the chemical and biological reactions of certain nitrosamines; b) preparation and characterization of some possible products of metabolic activation of carcinogenic N-nitroso compounds; c) mechanisms of environmental synthesis and degradation of N-nitroso compounds; d) preparation of novel nitrosamines for biological and biochemical testing; e) derivatization reactions of N-nitroso compounds. Possible implications of this work with respect to the overall goal of human cancer prevention will be considered.